Low prevalence of Babesia hongkongensis infection in community and privately-owned cats in Hong Kong.

Domestic cats are susceptible to infection with at least 11 species of Babesia. In Hong Kong, where dogs are commonly infected with B. gibsoni, a single infection in a cat by a novel species, B. hongkongensis, was reported previously. The aim of this study was to investigate the frequency of Babesia spp. detection in cats in Hong Kong. Residual blood-derived DNA from healthy free-roaming community cats (n = 239), and privately-owned cats with and without anaemia undergoing diagnostic investigations (n = 125) was tested for Babesia spp. DNA using a pan-Babesia PCR targeting mitochondrial Cytochrome B, and a B. hongkongensis specific PCR targeting 18S rRNA. Positive samples were confirmed by sequencing and comparative sequence analysis against the GenBank nucleotide database. Babesia hongkongensis was detected in 4/239 (1.7 %) community cats, and 0/125 (0.0 %) privately-owned cats. Babesia gibsoni was detected in 0/239 community cats and 1/125 (0.8 %) privately-owned cats. Cats infected with B. hongkongensis were clinically healthy at the time of sampling. The B. gibsoni-infected cat was anaemic and thrombocytopenic. Cats in Hong Kong can be infected with B. hongkongensis and B. gibsoni, albeit at low frequency. The tick vector for B. hongkongensis is yet to be identified.

Effects of a novel bites, steps and eating rate-focused weight loss randomised controlled trial intervention on body weight and eating behaviours.

BACKGROUND: Eating rate (ER), comprising the amount of food consumed per unit of time, is associated with obesity and energy intake (EI). METHODS: The present study tested whether adding a self-monitoring wearable device to a multifaceted 8-week weight loss intervention increased weight loss. In addition, the device's effect on secondary change outcomes in EI, ER and estimated energy expenditure was explored. Tertiary outcomes included examining eating behaviours measured by the Weight-Related Eating Questionnaire (WREQ). Seventy-two adults who were overweight or obese [mean (SD) age, 37.7 (15.3) years; body mass index, 31.3 (3.2) kg m-2 ] were randomised into two groups: intervention workbook plus device (WD) or intervention workbook only (WO). Three 24-h dietary recalls were obtained before weeks 0 and 8. Participants were weighed, consumed a test meal and completed 7-day Physical Activity Recall and WREQ at weeks 0 and 8. RESULTS: There was no significant difference between WD and WO groups with respect to weight change [-0.46 (1.11) vs. 0.26 (0.82) kg, respectively], ER, EI, energy expenditure or WREQ scores, although there were significant changes over time, and within-group changes on all of these variables. At week 8, participants were dichotomised into weight loss or weight stable/gainers groups. A significant time by group change was seen in susceptibility to external cues scores, with significant time effects for susceptibility and restraint. CONCLUSIONS: An intervention focused on reducing ER, energy density and increasing steps was effective for weight loss, although the wearable device provided no additional benefit. Participants with higher susceptibility to external eating may be more responsive to this intervention.

Shelter-housed cats show no evidence of faecal shedding of canine parvovirus DNA.

Canine parvovirus (CPV) and feline panleukopenia virus (FPV) are deoxyriboncucleic acid (DNA) viruses in the taxon Carnivore protoparvovirus 1. Exposure of cats to either CPV or FPV results in productive infection and faecal shedding of virus. Asymptomatic shedding of CPVs by one-third of shelter-housed cats in a UK study suggests that cats may be an important reservoir for parvoviral disease in dogs. The aim of this cross-sectional study was to determine the prevalence of faecal shedding of CPVs in asymptomatic shelter-housed cats in Australia. Faecal samples (n=218) were collected from cats housed in three shelters receiving both cats and dogs, in Queensland and NSW. Molecular testing for Carnivore protoparvovirus 1 DNA was performed by polymerase chain reaction (PCR) amplification followed by DNA sequencing of the VP2 region to differentiate CPV from FPV. Carnivore protoparvovirus 1 DNA was detected in only four (1.8%, 95% confidence interval 0.49-4.53%) faecal samples from a single shelter. Sequencing identified all four positive samples as FPV. Faecal shedding of CPV by shelter-cats was not detected in this study. While the potential for cross-species transmission of CPV between cats and dogs is high, this study found no evidence of a role for cats in maintaining CPV in cat and dog populations through faecal shedding in the regions tested.

Evaluation of Serum Aspergillus-Specific Immunoglobulin A by Indirect ELISA for Diagnosis of Feline Upper Respiratory Tract Aspergillosis.

BACKGROUND: Serological tests for diagnosis of aspergillosis in immunocompetent humans and animals are based on Aspergillus-specific IgG (As-IgG). In humans with chronic pulmonary aspergillosis, As-IgA may be detectable even if IgG titers are negative. Cats with upper respiratory tract aspergillosis (URTA) have detectable As-IgG, but their ability to mount an IgA response and its diagnostic utility are unknown. OBJECTIVES: To determine whether serum As-IgA can be detected in cats with URTA and evaluate its diagnostic utility alone or combined with As-IgG. ANIMALS: Twenty-three cats with URTA (Group 1), 32 cats with other respiratory diseases (Group 2), and 84 nonrespiratory controls (Group 3). METHODS: Serum As-IgA and As-IgG was measured by indirect ELISA. Optimal cutoff values were determined by receiver-operating curve analysis. Sensitivity (Se) and specificity (Sp) for URTA diagnosis were determined. RESULTS: Serum IgA was detected in 91.3% of Group 1 cats. The Se of IgA detection was 78.3% and Sp was 96.9% for Group 2, 85.7% for Group 3 and 88.8% for Group 2 and 3 combined. Assay Se for IgG was 100% and Sp was 92.2%. Using combined IgA and IgG results at cutoffs optimized for Sp for IgA and Se for IgG and combined controls (Groups 2 and 3), Se for diagnosis was 100% and Sp was 91.4%. CONCLUSION AND CLINICAL IMPORTANCE: Most cats with URTA have serum As-IgA antibodies that can be detected by ELISA. Paired measurement of serum As-IgA and IgG shows no benefit for diagnosis of feline URTA over IgG alone.

Immunohistochemical Analysis of Leucocyte Subsets in the Sinonasal Mucosa of Cats with Upper Respiratory Tract Aspergillosis.

Leucocyte populations in the sinonasal mucosa of cats with and without upper respiratory tract aspergillosis were compared using immunohistochemistry and computer-aided morphometry. Inflammation was identified in the nasal mucosa of all affected cats, comprising predominantly of lymphoplasmacytic infiltration of the lamina propria associated with epithelial proliferation and degeneration. There was intense and diffuse expression of class II antigens of the major histocompatibility complex, associated with sites of hyphal invasion with hyperplasia and ulceration of the epithelium adjacent to fungal elements. Significantly more CD79b(+) cells, total lymphocytes, immunoglobulin (Ig)-expressing cells and MAC387(+) cells infiltrated the epithelium and more IgG(+) cells and total Ig-expressing cells infiltrated the lamina propria in affected cats compared with controls. Importantly, the inflammatory profile in affected cats was not consistent with the T helper (Th)1 and Th17 cell-mediated response that confers protective acquired immunity against invasive aspergillosis in dogs and people and in murine models of the infection. This finding may help to explain the development of invasive aspergillosis in systemically immunocompetent cats.

High prevalence of Felis catus gammaherpesvirus 1 infection in haemoplasma-infected cats supports co-transmission.

Felis catus gammaherpesvirus 1 (FcaGHV1), a potential feline pathogen, has been identified in domestic cats from USA, Asia-Pacific and Central Europe. Transmission of FcaGHV1 during territorial encounters, a route not typical for gammaherpesviruses, is suggested by risk factor analyses from some regions. The aim of this study was to investigate the relationship between FcaGHV1 detection and risk factors, including haemoplasma co-infections, among UK cats to better understand transmission and global distribution of FcaGHV1. FcaGHV1 DNA was detected in blood samples from UK cats (11.56%; 95% confidence interval [CI], 7.47-16.84; n = 199). Logistic regression analyses showed that entire male cats were more likely to be FcaGHV1 positive than neutered male cats (odds ratio, 3.60; 95% CI, 1.22-10.46). Samples positive for DNA from any of three haemoplasma species had 19 times greater odds for testing positive for FcaGHV1 than haemoplasma negative cats in multivariable analyses after adjusting for age, sex and neuter status. Domestic cats in the UK can be infected with FcaGHV1, confirming that this virus is globally endemic. The identification of neuter status as a risk factor for FcaGHV1 detection provides further evidence to support transmission of this virus during territorial encounters and co-transmission with haemoplasmas is suggested.

The ionic mechanism of membrane potential oscillations and membrane resonance in striatal LTS interneurons.

Striatal low-threshold spiking (LTS) interneurons spontaneously transition to a depolarized, oscillating state similar to that seen after sodium channels are blocked. In the depolarized state, whether spontaneous or induced by sodium channel blockade, the neurons express a 3- to 7-Hz oscillation and membrane impedance resonance in the same frequency range. The membrane potential oscillation and membrane resonance are expressed in the same voltage range (greater than -40 mV). We identified and recorded from LTS interneurons in striatal slices from a mouse that expressed green fluorescent protein under the control of the neuropeptide Y promoter. The membrane potential oscillation depended on voltage-gated calcium channels. Antagonism of L-type calcium currents (CaV1) reduced the amplitude of the oscillation, whereas blockade of N-type calcium currents (CaV2.2) reduced the frequency. Both calcium sources activate a calcium-activated chloride current (CaCC), the blockade of which abolished the oscillation. The blocking of any of these three channels abolished the membrane resonance. Immunohistochemical staining indicated anoctamin 2 (ANO2), and not ANO1, as the CaCC source. Biophysical modeling showed that CaV1, CaV2.2, and ANO2 are sufficient to generate a membrane potential oscillation and membrane resonance, similar to that in LTS interneurons. LTS interneurons exhibit a membrane potential oscillation and membrane resonance that are both generated by CaV1 and CaV2.2 activating ANO2. They can spontaneously enter a state in which the membrane potential oscillation dominates the physiological properties of the neuron.

Detection of Aspergillus-specific antibodies by agar gel double immunodiffusion and IgG ELISA in feline upper respiratory tract aspergillosis.

Feline upper respiratory tract aspergillosis (URTA) is an emerging infectious disease. The aims of this study were: (1) to assess the diagnostic value of detection of Aspergillus-specific antibodies using an agar gel double immunodiffusion (AGID) assay and an indirect immunoglobulin G (IgG) ELISA; and (2) to determine if an aspergillin derived from mycelia of Aspergillus fumigatus, Aspergillus niger and Aspergillus flavus can be used to detect serum antibodies against cryptic Aspergillus spp. in Aspergillus section Fumigati. Sera from cats with URTA (group 1: n = 21) and two control groups (group 2: cats with other upper respiratory tract diseases, n = 25; group 3: healthy cats and cats with non-respiratory, non-fungal illness, n = 84) were tested. Isolates from cats with URTA comprised A. fumigatus (n = 5), A. flavus (n = 1) and four cryptic species: Aspergillus felis (n = 12), Aspergillus thermomutatus (Neosartorya pseudofischeri, n = 1), Aspergillus lentulus (n = 1) and Aspergillus udagawae (n = 1). Brachycephalic purebred cats were significantly more likely to develop URTA than other breeds (P = 0.013). The sensitivity (Se) of the AGID was 43% and the specificity (Sp) was 100%. At a cut-off value of 6 ELISA units/mL, the Se of the IgG ELISA was 95.2% and the Sp was 92% and 92.9% for groups 2 and 3 cats, respectively. Aspergillus-specific antibodies against all four cryptic species were detected in one or both assays. Assay Se was not associated with species identity. Detection of Aspergillus-specific antibodies by IgG ELISA has high Se and Sp for diagnosis of feline URTA.

Evaluation of polybrominated diphenyl ethers (PBDEs) in matched cat sera and house dust samples: investigation of a potential link between PBDEs and spontaneous feline hyperthyroidism.

The cause of feline hyperthyroidism (FH), a common endocrinopathy of domestic cats, is unknown. A potential association between exposure to environmental contaminants polybrominated diphenyl ethers (PBDEs) and FH was investigated. The median serum level for the sum of congeners BDE-47, BDE-99, BDE-153, BDE-154 and BDE-183 (Σ5) in hyperthyroid and euthyroid cats was 82 and 174 ng g(-1)lw respectively with no significant difference in PBDE levels or profiles between groups. Overall, the median (min to max) concentration of PBDEs in cat serum (n=65) was 118 ng g(-1)lw (5-5260 ng g(-1)lw), which is approximately 10 times higher than that observed in the Australian human population. Furthermore, congener composition in feline serum samples was dominated by congener BDE-99, followed by BDE-47 then BDE-153 which differs from results of human biomonitoring. There was no correlation between PBDE levels in feline serum samples and matched house dust samples (n=25). However the similarity of BDE-47/99 ratio in each matrix suggests dust is likely the dominant exposure. Calculation of the daily exposure dose via dust ingestion for cats equated to a mean of 33 ng kg(-1) bw d(-1) (0.2-150 ng kg(-1) bw d(-1)). Differences in exposure estimates for Australian and US cats, based on dust ingestion alone, are consistent with the observed differences in body burdens. Our results do not support a role for PBDE exposure in the aetiopathogenesis of FH.

Computed tomographic features of feline sino-nasal and sino-orbital aspergillosis.

Feline upper respiratory tract aspergillosis (URTA) occurs as two distinct anatomical forms, namely, sino-nasal aspergillosis (SNA) and sino-orbital aspergillosis (SOA). An emerging pathogen, Aspergillus felis, is frequently involved. The pathogenesis of URTA, in particular the relationship between the infecting isolate and outcome, is poorly understood. In this study, computed tomography was used to investigate the route of fungal infection and extension in 16 cases (SNA n = 7, SOA n = 9) where the infecting isolate had been identified by molecular testing. All cases had nasal cavity involvement except for one cat with SNA that had unilateral frontal sinus changes. There was a strong association between the infecting species and anatomic form (P = 0.005). A. fumigatus infections remained within the sino-nasal cavity, while cryptic species infections were associated with orbital and paranasal soft-tissue involvement and with orbital lysis. Cryptic species were further associated with a mass in the nasal cavity, paranasal sinuses or nasopharynx. Orbital masses showed heterogeneous contrast enhancement, with central coalescing hypoattenuating foci and peripheral rim enhancement. Severe, cavitated turbinate lysis, typical of canine SNA, was present only in cats with SNA. These findings support the hypothesis that the nasal cavity is the portal of entry for fungal spores in feline URTA and that the route of extension to involve the orbit is via direct naso-orbital communication from bone lysis. Additionally, a pathogenic role for A. wyomingensis and a sinolith in a cat with A. udagawae infection are reported for the first time.

Clinical findings and survival in cats naturally infected with feline immunodeficiency virus.

BACKGROUND: The clinical course and outcome of natural feline immunodeficiency virus (FIV) infection are variable and incompletely understood. Assigning clinical relevance to FIV infection in individual cats represents a considerable clinical challenge. OBJECTIVE: To compare signalment, hematologic and biochemical data, major clinical problem, and survival among client-owned, FIV-infected, and uninfected domestic cats. ANIMALS: Client-owned, domestic cats tested for FIV (n = 520). METHODS: Retrospective, case control study. Logistic regression analyses were conducted to identify risk factors for FIV infection and to compare hematologic and biochemical data between cases and controls, after adjusting for potential confounders. Survival times were compared using Kaplan-Meier curves. RESULTS: The prevalence of FIV infection was 14.6%. Mixed breed, male sex, and older age were risk factors for FIV infection. Hematologic abnormalities, biochemical abnormalities or both were common in both FIV-infected and uninfected cats. Lymphoid malignancies were slightly more common in FIV-infected than uninfected cats. Survival of FIV-infected cats was not significantly different from that of uninfected cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Multiple hematologic and biochemical abnormalities are common in old, sick cats regardless of their FIV status. Their presence should not be assumed to indicate clinical progression of FIV infection. A negative effect of FIV on survival was not apparent in this study.

Evaluation of serum galactomannan detection for diagnosis of feline upper respiratory tract aspergillosis.

Measurement of serum galactomannan (GM), a polysaccharide fungal cell-wall component, is a non-invasive test for early diagnosis of invasive aspergillosis in humans. Feline upper respiratory tract (URT) aspergillosis is an emerging infectious disease in cats. Diagnosis requires biopsy for procurement of tissue specimens for cytological or histological detection of fungal hyphae and for fungal culture. The aim of this study was to evaluate serum GM measurement as a non-invasive diagnostic test for URT aspergillosis in cats. A one-stage, immunoenzymatic sandwich ELISA was used to detect serum GM in 4 groups of cats; Group 1 (URT aspergillosis) - confirmed URT aspergillosis (n=13, sinonasal aspergillosis (SNA) n=6 and sino-orbital aspergillosis (SOA) n=7), Group 2 (URT other) - other URT diseases (n=15), Group 3 (ß-lactam) - cats treated with ß-lactam antibiotics for non-respiratory tract disease (n=14), Group 4a - healthy young cats (≤ 1 y of age, n=28), Group 4b - healthy adult cats (>1 y of age, n=16). One cat with SNA and two cats with SOA caused by an Aspergillus fumigatus-mimetic species, tested positive for serum GM. For a cut-off optical density index of 1.5, the overall sensitivity and specificity of the assay was 23% and 78% respectively. False positive results occurred in 29% of cats in Group 3 and 32% of cats in Group 4a. Specificity increased to 90% when Groups 3 and 4a were excluded from the analysis. Overall, serum GM measurement has a poor sensitivity but is a moderately specific, non-invasive screening test to rule out infection in patients with suspected feline upper respiratory tract aspergillosis.

Severe systemic hypertension in a cat with pituitary-dependent hyperadrenocorticism.

A seven-year-old Burmese cat was presented with sudden onset blindness. On physical examination, the cat had bilateral retinal detachment and severe systemic hypertension. Further clinical investigations revealed pituitary-dependent hyperadrenocorticism. Antihypertensive therapy was discontinued when the hypertension resolved after bilateral adrenalectomy. Systolic blood pressure remained normal until 19 months post-operatively when systemic hypertension recurred and was attributed to chronic kidney disease. The cat was euthanased 47 months after initial presentation. A pituitary adenoma was identified at post-mortem examination. This case illustrates that systemic hypertension can occur secondary to hyperadrenocorticism in the cat.

Sinonasal and sino-orbital aspergillosis in 23 cats: aetiology, clinicopathological features and treatment outcomes.

Aetiology, clinicopathological findings and treatment outcomes were documented in 23 cats (1.5-13 years of age) with sinonasal (SNA, n=6) or sino-orbital (SOA, n=17) aspergillosis. Cases recruited retrospectively and prospectively were included if fungal hyphae were identified on cytological or histological examination and the fungal pathogen was identified by PCR and DNA sequencing (ITS1 or ITS1-5.8S-ITS2 regions, rDNA gene cluster). Fungal culture was positive in 22/23 cases. In cases of SNA, the fungal pathogen was Aspergillus fumigatus (n=4), Neosartorya fischeri or A. lentulus (n=1) or a non-speciated Neosartorya spp. (n=1). In all cases of SOA (n=17), the fungal pathogen was identified as Neosartorya spp. Nine cats had brachycephalic conformation. Cats with SNA were more likely to be infected with A. fumigatus and had a better prognosis than cats with SOA.

Histopathological and immunohistochemical evaluation of 53 cases of feline lymphoplasmacytic enteritis and low-grade alimentary lymphoma.

Low-grade alimentary lymphoma (LGAL) is a recently described entity displaying many microscopical features similar to lymphoplasmacytic enteritis (LPE). The aim of this study was to review the histopathological and immunohistochemical features of LPE and LGAL to determine if specific features are useful in distinguishing between these disorders. Fifty-three cases of LPE (n=24) or LGAL (n=29) were recruited retrospectively and prospectively. Of the 24 cases of LPE, 12 were mild, seven were moderate and five were marked in severity. The ileum and jejunum were the most common sites affected for both LGAL and LPE (70-90% of cases). Involvement of the stomach was more common with LPE (29%) than LGAL (7%) (P<0.0001). Twelve cases of LGAL (41%) had evidence of concurrent LPE. Microscopical features significantly associated with LGAL were epitheliotropism, involvement of the muscularis propria and/or serosa, more severe infiltration and more severe changes to the villus and crypt architecture. Plasma cell infiltration within the mucosa, conversely, was a feature of LPE. Twenty-eight of the 29 cases of LGAL were of T-cell phenotype. While many LGAL and most LPE cases had a mixed infiltrate of T and B lymphocytes, LGAL cases had a clear predominance of the T-cell phenotype. Expression of class II molecules of the major histocompatibility complex by enterocytes did not differentiate between LGAL and LPE. In eight of 12 cases of moderate-marked LPE there was disparity in diagnosis by two pathologists regarding differentiation from LGAL, requiring assessment by a third pathologist to reach a consensus diagnosis. This demonstrates the inherent difficulty in differentiating LPE from LGAL on the basis of microscopical and immunohistochemical features alone. Other diagnostic tools such as clonality testing may assist in the definitive diagnosis of such cases.

Prevalence of Bartonella species, Rickettsia felis, haemoplasmas and the Ehrlichia group in the blood of cats and fleas in eastern Australia.

OBJECTIVES: To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' (Mhm) and 'Candidatus Mycoplasma turicensis' (Mtc) in cats and their fleas in eastern Australia. DESIGN AND PROCEDURE: Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. RESULTS: DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. CONCLUSIONS: This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.

Two distinct populations of projection neurons in the rat lateral parafascicular thalamic nucleus and their cholinergic responsiveness.

The lateral parafascicular nucleus (lPf) is a member of the intralaminar thalamic nuclei, a collection of nuclei that characteristically provides widespread projections to the neocortex and basal ganglia and is associated with arousal, sensory, and motor functions. Recently, lPf neurons have been shown to possess different characteristics than other cortical-projecting thalamic relay neurons. We performed whole cell recordings from lPf neurons using an in vitro rat slice preparation and found two distinct neuronal subtypes that were differentiated by distinct morphological and physiological characteristics: diffuse and bushy. Diffuse neurons, which had been previously described, were the predominant neuronal subtype (66%). These neurons had few, poorly-branching, extended dendrites, and rarely displayed burst-like action potential discharge, a ubiquitous feature of thalamocortical relay neurons. Interestingly, we discovered a smaller population of bushy neurons (34%) that shared similar morphological and physiological characteristics with thalamocortical relay neurons of primary sensory thalamic nuclei. In contrast to other thalamocortical relay neurons, activation of muscarinic cholinergic receptors produced a membrane hyperpolarization via activation of M(2) receptors in most lPf neurons (60%). In a minority of lPf neurons (33%), muscarinic agonists produced a membrane depolarization via activation of predominantly M(3) receptors. The muscarinic receptor-mediated actions were independent of lPf neuronal subtype (i.e. diffuse or bushy neurons); however the cholinergic actions were correlated with lPf neurons with different efferent targets. Retrogradely-labeled lPf neurons from frontal cortical fluorescent bead injections primarily consisted of bushy type lPf neurons (78%), but more importantly, all of these neurons were depolarized by muscarinic agonists. On the other hand, lPf neurons labeled by striatal injections were predominantly hyperpolarized by muscarinic agonists (63%). Our results indicate two distinct subpopulations of lPf projection neurons, and interestingly lPf neurons respond differentially to muscarinic receptor activation based on their axonal target.

Erythrocytic pyruvate kinase deficiency and AB blood types in Australian Abyssinian and Somali cats.

OBJECTIVE: To determine the frequency of the mutant pyruvate kinase (PK) allele, haematological parameters and AB blood types of Abyssinian and Somali cats in Australia. DESIGN: Complete blood cell and reticulocyte counts, DNA PK mutation testing and blood typing were performed in all cats. RESULTS: A total of 60 cats (36 Abyssinians, 24 Somalis) were included (37 females, 23 males). For the mutant PK allele, three female Somalis were homozygous (affected, 5%), 17 cats were heterozygous (carrier, 28%) and 40 cats tested negative (normal, 67%). Pedigree analysis revealed common ancestry of affected and many carrier cats. Of affected cats, two had regenerative anaemias and all had reticulocytosis (range 64-390 x 10(9)/L; P < 0.001 compared with normal or carrier cats). The only consistent historical sign was lethargy. One affected cat was euthanased 18 months after testing, because of anaemia, neutropenia, anorexia and weight loss. The mutant allele frequency was 0.19 overall (0.29 in Somalis, 0.13 in Abyssinians). All cats had blood type A. The commercial blood typing card method incorrectly identified 12 cats as having type AB blood. CONCLUSIONS: The frequency of the mutant PK allele is high in Australia. Screening for PK deficiency is indicated before mating and in individual cats of these breeds, even in the absence of anaemia and especially when there is reticulocytosis. Although all cats in the present study had blood type A, blood type B is common in these breeds worldwide. Retyping of any AB typed cats by a laboratory technique is recommended.

Intracranial empyema: literature review and two novel cases in cats.

OBJECTIVES: To review the literature on intracranial empyema and report two new cases in cats. METHODS: Literature review and case reports. RESULTS: Intracranial empyema has been rarely reported in small animals. In two novel cases in cats, the route of infection was postulated to be local extension from a retrobulbar abscess of odontogenic origin in one case and direct inoculation from a penetrating bite wound to the skull, confirmed at post-mortem examination, in the other. On magnetic resonance imaging of the first case, there was a contrast-enhancing large extra-axial fluid collection overlying the right cerebral hemisphere, consistent with subdural empyema. Infection was caused by an Actinomyces spp. This is the first report of successful treatment of intracranial empyema by craniotomy, drainage and antibiotics. CLINICAL SIGNIFICANCE: Intracranial empyema is a neurosurgical emergency. Favourable outcomes may be achieved with surgical decompression, antimicrobial therapy and intensive care.